flash[:notice] = "You can stop rolling your own now."
Simple flash hash implementation for Rack apps.
Here's how to use it.
You can access flash entries via env['x-rack.flash']. You can treat it either
like a regular flash hash:
env['x-rack.flash'][:notice] = 'You have logged out.'
Or you can pass the :accessorize option to declare your flash types. Each of
these will have accessors defined on the flash object:
use Rack::Flash, :accessorize => [:notice, :error]
# Set a flash entry
env['x-rack.flash'].notice = 'You have logged out.'
# Get a flash entry
env['x-rack.flash'].notice # => 'You have logged out.'
# Set a a flash entry for only the current request
env['x-rack.flash'].notice! 'You have logged out.'
Sample rack app:
get = proc { |env|
[200, {},
env['x-rack.flash'].notice || 'No flash set. Try going to /set'
]
}
set = proc { |env|
env['x-rack.flash'].notice = 'Hey, the flash was set!'
[302, {'Location' => '/'},
'You are being redirected.'
]
}
builder = Rack::Builder.new do
use Rack::Session::Cookie
use Rack::Flash, :accessorize => true
map('/set') { run set }
map('/') { run get }
end
Rack::Handler::Mongrel.run builder, :Port => 9292
If you're using Sinatra, you can use the flash hash just like in Rails:
require 'sinatra/base'
require 'rack-flash'
class MyApp < Sinatra::Base
enable :sessions
use Rack::Flash
post '/set-flash' do
# Set a flash entry
flash[:notice] = "Thanks for signing up!"
# Get a flash entry
flash[:notice] # => "Thanks for signing up!"
# Set a flash entry for only the current request
flash.now[:notice] = "Thanks for signing up!"
end
end
If you've got any ideas on how to simplify access to the flash hash for vanilla Rack apps, let me know. It still feels a bit off to me.
By default Rack::Flash has slightly different behavior than Rails in that it
doesn't delete entries until they are used. If you want entries to be cleared
even if they are not ever accessed, you can use the :sweep option:
use Rack::Flash, :sweep => true
This will sweep stale flash entries, whether or not you actually use them.